The invention provides a process for preparing molybdenum and tungsten oxyhalide compounds which are useful in the deposition of molybdenum and tungsten containing films on various surfaces of microelectronic devices. In the process of the invention, a molybdenum or tungsten trioxide is heated in either a solid state medium or in a melt-phase reaction comprising a eutectic blend comprising alkaline and/or alkaline earth metal salts. The molybdenum or tungsten oxyhalides thus formed may be isolated as a vapor and crystallized to provide highly pure precursor compounds such as MoO.sub.2Cl.sub.2.

The invention provides a process for preparing molybdenum and tungsten oxyhalide compounds which are useful in the deposition of molybdenum and tungsten containing films on various surfaces of microelectronic devices. In the process of the invention, a molybdenum or tungsten trioxide is heated in either a solid state medium or in a melt-phase reaction comprising a eutectic blend comprising alkaline and/or alkaline earth metal salts. The molybdenum or tungsten oxyhalides thus formed may be isolated as a vapor and crystallized to provide highly pure precursor compounds such as MoO.sub.2Cl.sub.2.

Tungsten precursors with high purity and methods for purifying tungsten precursors are provided. The method for purifying a precursor may comprise at least one of the following steps: obtaining a source vessel containing WCl.sub.4, WOCl.sub.4, and one of WCl.sub.5 or WCl.sub.6; separating the WCl.sub.5 or the WCl.sub.6 from at least a first portion of the WOCl.sub.4; separating the WCl.sub.5 or the WCl.sub.6 from at least a second portion of the WOCl.sub.4; recovering a precursor in a collection vessel; or any combination thereof.

Tungsten precursors with high purity and methods for purifying tungsten precursors are provided. The method for purifying a precursor may comprise at least one of the following steps: obtaining a source vessel containing WCl.sub.4, WOCl.sub.4, and one of WCl.sub.5 or WCl.sub.6; separating the WCl.sub.5 or the WCl.sub.6 from at least a first portion of the WOCl.sub.4; separating the WCl.sub.5 or the WCl.sub.6 from at least a second portion of the WOCl.sub.4; recovering a precursor in a collection vessel; or any combination thereof.

A precursor comprises a tungsten precursor and a carbon-containing material. The precursor comprises less than 0.02% by weight of the carbon-containing material based on a total weight of the precursor. A method for purifying a tungsten precursor may comprise at least one of the following steps: obtaining a source vessel containing a tungsten precursor and a carbon-containing material; separating the tungsten precursor from at least a first portion of the carbon-containing material; recovering a precursor in a collection vessel; or any combination thereof.

A precursor comprises a tungsten precursor and a carbon-containing material. The precursor comprises less than 0.02% by weight of the carbon-containing material based on a total weight of the precursor. A method for purifying a tungsten precursor may comprise at least one of the following steps: obtaining a source vessel containing a tungsten precursor and a carbon-containing material; separating the tungsten precursor from at least a first portion of the carbon-containing material; recovering a precursor in a collection vessel; or any combination thereof.

Conditioning of tungsten pentachloride to form specific crystalline phases is disclosed. The specific crystalline phases permit stable vapor pressures over extended periods of time during vapor deposition and etching processes.

Conditioning of tungsten pentachloride to form specific crystalline phases is disclosed. The specific crystalline phases permit stable vapor pressures over extended periods of time during vapor deposition and etching processes.

Synthesis of tungsten pentahalide compositions having low impurity profiles are disclosed. The specific impurity profile permits deposition of high purity tungsten-containing films using vapor deposition processes or other semiconductor manufacturing processes without introduction of performance-impacting contaminants.

Synthesis of tungsten pentahalide compositions having low impurity profiles are disclosed. The specific impurity profile permits deposition of high purity tungsten-containing films using vapor deposition processes or other semiconductor manufacturing processes without introduction of performance-impacting contaminants.